 //********************************************************************
 // ParameterTester.java           Author:20172323wyh
 //
 // Demonstrates the effects of passing various types of parameters.
 //********************************************************************

 public class ParameterTester
 {
    //-----------------------------------------------------------------
    // Sets up three variables (one primitive and two objects to
    // serve as actual parameters to the changeValues method. Prints
    // their values before and after calling the method.
    //-----------------------------------------------------------------
    public static void main(String[] args)
    {
       ParameterModifier modifier = new ParameterModifier();
  
       int a1 = 111;
       Num a2 = new Num(222);
       Num a3 = new Num(333);

       System.out.println("Before calling changeValues:");
       System.out.println("a1\ta2\ta3");
       System.out.println(a1 + "\t" + a2 + "\t" + a3 +"\n");

       modifier.changeValues(a1, a2, a3);
       
       System.out.println("After calling changeValues:");
       System.out.println("a1\ta2\ta3");
       System.out.println(a1 + "\t" + a2 + "\t" + a3 +"\n");
    }
 }
